Process of making acetylene chlorid.



HEINRICH PREUHT, OF NEUSTASSFUR'J.. GERMANY.

PROCESS OF MAKING ACETYLENE CHLORID- Specification of Letters Patent.

Patented April 10, 1906.

Application filed May 22, 1905. Serial No: 261,663.

To all whom it may concern:

Be it known that I, HEINRICH PRECHT, a subject of the Kin of Prussia, German Emperor, residing at 0. 7 Neustassfurt, Germany, have invented certain new and useful Improvements in Processes of Making Acetylene'Chlorid; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

While acetylene combines directly with bromin without difficulty, chlorin, on the other hand, owing to its greater affinity for hydrogen acts so strongly on acetylene that a view of the high price of this compound is likely to preclude the utilization of the reac tion. This drawback also applies to a pro posed mixture of ethylene chlorid and aluminium chlorid, into which mixture chlorin and acetyleneare to be simultaneously introduced. This mixture further has the disadvantage that the higher chlorination taking place at a higher temperature about 120 centigrade-is only possible in an autoclave, as the ethylene chlorid boils at 84 centigrade. The two ases would therefore have to be introduced Into the mixture by means of considerable pressure, which, however,

wouldbe dangerous, since acetylene, if compressed to two or more atmospheres, acts like an explosive. Besides when introducing chlorin and acetylene simultaneously great difiiculties are encountered, these gases acting on one another so rapidly as to cause'explosions. I have found that all these drawacks are avoided by using chlorid of sulfur with an addition of a contact substance, as finely-divided iron, compounds of iron, or the like. Chlorid of sulfur without such ingredients fails to act. Chlorid of sulfur having a high. boiling-point, (138 centigrade,) even hexachlorid of ethane may be produced, de-

pending upon the temperature at which chlo- 5 5 rination is efiected. In consequence of the low price of chlorid of sulfur and in view of the fact that it can be fully recovered it ofiers many advantages as compared with other substances.

In carrying out my invention acetylene is introduced into a mixture of chlorid of sulfur and powdered or finely-divided iron. temperature is reduced by coolin if ethane tetrachlorid is to be produced. if, for example, ethane hexachlorid is to be obtained, the mixture is heated. Should acetylene be incompletely or imperfectly absorbed, a stron flow of chlorin to nearly saturation is intro uced. The introduction of acetylene and chlorin is repeated a number of times alternately in such away that chlorin and acetylene cannot act directly on one another.

In order to produce ethane tetrachlorid, the reaction mixture is preferably saturated finally with acetylene, the tetrachlorid formed,boiling at 147 centigrade, is distilled off either by itself or driven off by steam, While the sulfur which remains is converted in the known manner into chlorid of sulfur for reuse in the process.

The reactions taking place may be explained by the following: When chlorin reacts on the men-chlorid of sulfur, higher chlorids are formed:

s2ct+2c1=2sct S2Cl2+6Gl 2SUh Now when acetylene reacts upon a mixture of these chlorids-41. 2., S 0 S0,, and SCL as describedtetrachlorethane is produced with the separation of sulfur:

2s2c12+ can: canola 4s 2so12+ can canola as I SOI4+G2H2 C2H2Gll+ S The separated sulfur is again converted, by means of chlorin, into monochlorid:

and by the first reaction into higher chlorids again.

It cannot be stated which of the described reactions operate most advantageously to produce the tetrachlorethane. It appears that all of the reactions take'place at the same time. I

- For the purpose 0 roducing, for example, ethane hexachlorid, (EllOIld of sulfur is referably saturated finally with chlorin at oiling temperature. When coolin ,hexachlorid crystallizes out of the liquid t us obtained,

The

which crystals arefurther purified by .pressl lng out and subliming or distilling with steam or recrystalizin from a suitable solvent for example, acohol. The liquid pressed out consists in general of chlorid of sulfur and dissolved ethane hexachlorid (which could also be separated by fractionation) is after addition of iron powder a ain treated With acetylene and chlorin. 0 course the reactlon mixture can be saturated finally with acetylene, whereupon the ethane hexachlorid (bo1l1ngpoint 185 centigrade) is separated from the sulfur (boiling-point 448) by distillation, driving it off with steam or by extraction.-

Having thus described my invention, What with acetylene, substantially as described.

2. The process of chlorinating acetylene, which consists in reacting upon a mixture of chlorid of sulfur and finely-divided iron, with acetylene, substantially as described.-

3. The process of chlorinating acetylene, which consists in reacting upon a mixture of chlorid of sulfur and a contact substance with acetylene at a temperature sufficient to produce the chlorid required, substantially as described.

4. The process of chlorinating acetylene, which consistsin reacting upon a mixture of chlorid of sulfur and a contact substance al ternately with acetylene and chlorin, substantially as described.

In testimony that I claim the foregoing as my invention I have signed my name in presence of two subscribin Witnesses.

- HEI NRICH PRECHT. Witnesses:

ADoLF ScHLoss,. JAMEs L. A. BURRELL. 

